The problem seems to be the same in latest stable version of Opera portable 11.11, and latest beta version, which is 11.50 beta 1 portable.
When I first start Opera Browser, the default interface language is English. Then I go to Menu->Settings->Preferences (or just press Ctrl + F12) and on first tab, on the bottom, where description is: "Select your preferred language for Opera and webpages" I select my preferred language (which is Polish for me) on drop down menu. Then I click OK.
The interface language changes to Polish, and everything seems fine, until i close the browser, and start it again, then language setting resets to English.
All other settings saves well, and remain unchanged after browser restart, only language always resets.
Is it a bug, or I am just doing something wrong?
If you are running it from the PortableApps.com Platform, it will automatically select the language; this means that if you run the Platform in Polish, it will make Opera run in Polish. In the next version of the Platform, there will be a way to disable automatic language switching.
I am a Christian and a developer and moderator here.
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